JPS6324096A - Countercurrent electrolyte injector - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a surface treatment device for pickling, oil removal, phosphoric acid treatment, etc.
In particular, it relates to a device for electroplating field pieces.

[Conventional technology]

Electrogalvanizing systems include one or more electrolytic cells filled with an electrolyte solution in which the steel strip is immersed and coated on one or both sides thereof. The billet passes over a conductor roll that is charged by a cathode that is half immersed in an electrolyte. A soluble zinc anode is immersed in an electrolyte and processed parallel to, but separated from, the conductor roll. Guided by conductor rolls, the billet passes through the gap between these rolls and the soluble zinc anode.

A significant drawback of this device is that the conductor roll is not sufficiently renewed in the space between the zinc anodes, resulting in depletion of the catholyte coating. This consumption is guided by current density limitations. The electrolyte in this space becomes saturated as the adhesive tension induces a significant reduction in the velocity of the billet relative to the solution. The productivity of electrogalvanizing systems thus deteriorates.

In order to overcome such deficiencies and to increase the velocity and current density of the billet, a countercurrent injection device is disclosed in European Patent EP O,125,707, U.S. Patent No. 3.9.
75.242 and 4,500,400 and British Patent No. 2,147,009, in which the electrolyte is injected backwards into the space between the anode and the billet. be done.

When these countercurrent electrolyte injection devices are placed on the side where the rising billet leaves the cell, these injection nozzles are placed below the surface of the bath (US Pat. No. 4,500,400).

Known electrolyte injection devices have serious deficiencies that are detrimental to the nature of the coating. In fact, these known injectors blow air into the space between the billet and the anode. A flat, rectangular injection nozzle is provided, the end of which is split or perforated over its entire length, so that the electrolyte is injected in the form of a plate or in the form of multiple jets. The injection nozzle is placed parallel to the billet, close to it and between it and the top of the anode. Because the injection nozzle is below the liquid level of the bath and the electrolyte leaves the nozzle at high speed,
A low-pressure area is created at the bath level by the pumping effect. Since the space between the billet and the nozzle is relatively small, the flow rate of electrolyte through the billet and nozzle tip is insufficient to compensate for this pressure drop.

Therefore, a channel is formed in the liquid level of the bath, and air is sucked into the air between the steel piece and the anode.

The first solution proposed in this field is to submerge the injector relatively deeply or completely in the electrolyte to reduce the pumping effect. This solution is not acceptable
This is because it results in a reduction in the effective length of the anode. It also requires the top of the anode to be submerged, preventing the operator from visually checking the placement of the anode.

Another way to avoid depletion of the electrolyte film that forms the cathode is to widen the gap between the anode and the conductor roll. The drawback of this solution is the high power consumption.

[Problem that the invention seeks to solve]

It is therefore an object of the present invention to overcome the above-mentioned deficiencies of known countercurrent injectors without changing the gap between the anode and the conductor roll, and to transfer the electrolyte throughout the space between the anode and the steel billet guided by the conductor roll. The aim is to ensure that the flow rate is sufficient to cover the area.

[Means for solving problems]

In order to achieve the above object, the present invention provides an injector having a plurality of injection tubes separated from each other to supply a sufficient flow rate of electrolyte.

〔Example〕

The features and advantages of the invention will be explained in more detail below with reference to the accompanying drawings, which show examples of embodiments.

The injector of the invention comprises at least one electrolyte artificial duct 1, the number and diameter of which duct 1 depends on the length of the injector, which depends on the length of the cathodic conductor roll through which the steel billet 14 passes; The distance between the soluble anode 15 and the steel piece 14 (second
(Figure) varies according to the flow rate of electrolyte required to ensure complete coverage. This duct 1 has a central chamber 2 with a circular cross section.
distribute the electrolyte flow as desired. The central chamber 2 extends over the entire length of the injector and is closed at both ends by closures 3. This central chamber 2 includes a plurality of openings 4 cut into the inner wall 5 of the injector.

These openings 4 are coaxial with the central chamber 2 and open over its entire length into a surrounding peripheral chamber 6, which serves to homogenize the flow of the electrolyte. An opening 4 is provided near the barrier 7 at the bottom of the central chamber 2 to direct the flow of electrolyte in the peripheral chamber 6 in a single direction.

In order to maintain the coaxial arrangement of both chambers 2, 6, a sufficient number of centering pins 8 are inserted into the peripheral chamber 6.

The flow of electrolyte is directed by the peripheral chamber 6 towards the nozzle 9;
This nozzle 9 is provided with a plurality of holes 10. A basic feature of the invention is that the nozzle 9 is extended by an injection tube 11 . In fact, unlike known injectors which are provided with a single flat square cross-section injection nozzle, the end of which is split over its entire width or drilled with multiple holes, the injector of the present invention has multiple The injection tube 11 has a comb shape. These injection tubes 1
1 is configured such that the electrolyte in the electrolytic bath 12 flows freely between them. The width of the anode top 15 is reduced to ensure sufficient flow of electrolyte from the electrolytic bath into the space between the roll and the anode.

In a preferred embodiment of the invention, the end of each injection tube is flattened like a fish's tail fin to allow more uniform injection of the electrolyte.

The total cross-sectional area of the gap between the injection tubes 110 is dimensioned such that the pressure drop occurring between the billet 14 and the injector is sufficiently damped, and (possibly) undesirable suction of air between the capacitive anode 15 and the billet 14 is avoided. remove. The injection tube 11 is preferably detachable from the nozzle 9.

[Brief explanation of drawings]

FIG. 1 is a partial front view of the construction of the present invention as seen in the direction of the arrow (■) in FIG. 2, and FIG. 2 is a sectional view taken along the line U--U in FIG. 1. ■...Fluid inlet duct, 2...Central fluid distribution chamber (
central chamber), 3... closing body, 4... opening, 5... inner wall, 6... outer peripheral chamber, 7... barrier, 8... centering pin, 9... nozzle, DESCRIPTION OF SYMBOLS 10... Hole, 11... Injection pipe, 12... Electrolytic bath, 14... Steel piece, 15... Soluble anode.

Claims (5)

[Claims] (1) at least one fluid inlet duct (1), a central fluid distribution chamber (2) extending along the entire length of the fuselage into which the inlet duct (1) is inserted, and said central chamber in the inner wall (5) of the fuselage; (2) a plurality of openings (4) bored at the lower end; an outer peripheral chamber (6) that is coaxial with the central chamber (2) and surrounds it along its entire length;
a barrier (7) disposed within the peripheral chamber (6) to direct the flow of fluid; and a nozzle (9) having a plurality of holes (10) perforated therein.
) and a plurality of injection tubes (11) extending the holes (10) and allowing free passage of the electrolyte from the electrolytic bath (12). (2) The device according to claim 1, wherein the end of the injection tube (11) has a circular cross section. (3) The device according to claim 1, wherein the end of the injection tube (11) has a flat plate in cross section. (4) Sufficient number of centering pins (8) in the peripheral chamber (6)
2. A device according to claim 1, characterized in that a. (5) comprising at least one injector according to any one of claims 1 to 4, a conductive roll and a soluble anode (15), the width of the top of the anode (15); An electrodeposition type electrolytic cell characterized by a reduction in .